incongruities. Meanwhile I have an experiment to propose." And leaning
close to the Inspector, notwithstanding the fact that there was nobody
within hearing and he knew it, he whispered a few words in his ear.

The Inspector stared.

"To-night?" he asked.

The detective nodded.

IX

WHILE THE CITY SLEPT

Night--the night of a great city with its myriad of garish lights and its
many curious and incongruous activities.

Who has not felt his imagination stirred by the contrasts thus
offered--contrasts never more apparent than at these hours of supposed
rest? Grim walls, with dimpled children sleeping behind them! Places of
merrymaking athrob with music and dazzling with jets of incandescent
light, with grief in the heart of the dancer and despair making raucous
the enforced laugh!

But nowhere in the great city of which we write on this night of May 23,
1913, was there to be found a scene of greater contradictions than in the
court and galleries of its famous museum.

Lighted as for a reception, the architectural beauties of its Moorish
arcades and carven balustrades flashed in full splendor. Gems of antique
art, casts in which genius had stored its soul and caused to live before
us the story of the ancients, pillars from desert sands, friezes from the
Parthenon and bas-reliefs from Nineveh and Heliopolis, filled every
corner, commanding the eye to satisfy itself in forms of deathless grace
or superhuman power. And no one to heed! Not an eye to note that the
Venus in one corner seemed to smile in the soft light with more than its
accustomed allurement, or that the armor in which kings had fought wore a
menacing sparkle exceeding that of other times and quieter days. Ghosts
of vanished ages might parade at will among the chattels of their time or
drain the iridescent beaker to their unknown gods--no one would have
noticed or turned aside to see. For there was something else within these
walls to-night for the men assembled there to look upon, and a story to
be read which shut the imagination upon the past by amply filling it with
the present.

What is this something? Let us follow the gaze of the half-dozen persons
grouped in front of the tapestry hanging in the northern gallery, and
see.

But first, of whom is this small and mystic group composed? Who are these
men who in the middle of the night, in the security of a completely
shuttered building, busy themselves, not with the inestimable treasures
s